CN111036030B

CN111036030B - Gas adsorption separation device

Info

Publication number: CN111036030B
Application number: CN201911343595.XA
Authority: CN
Inventors: 张传忠; 陈健
Original assignee: Shanghai Shencheng Environmental Protection Equipment Engineering Co ltd
Current assignee: Shanghai Shencheng Environmental Protection Equipment Engineering Co ltd
Priority date: 2018-07-09
Filing date: 2018-07-09
Publication date: 2022-04-12
Anticipated expiration: 2038-07-09
Also published as: CN110013736A; CN110013736B; CN111036030A

Abstract

The rotary wheel adsorber and the regenerative fixed bed adsorber in the existing gas adsorption concentration device are in a pair of contradiction when treating air polluted by volatile organic pollutants, namely high concentration ratio and low discharge concentration. The invention discloses a gas adsorption concentration device, which comprises an adsorption function module and other function modules, wherein the main function part of the adsorption function module is an adsorption sequence consisting of more than two adsorption units which are sequentially arranged, the adsorption sequence comprises a head end and a tail end, gas to be separated passes through the adsorption sequence from the head end to the tail end, the adsorption sequence is separated from the adsorption sequence and enters the other function modules after the adsorption units at the head end complete saturated adsorption on adsorbates, and the gas enters the adsorption sequence again from the tail end according to the sequence after desorption treatment is completed. The device enables the gas adsorption concentration device to have high concentration ratio and low emission concentration and can obviously reduce the energy consumption of the system.

Description

Gas adsorption separation device

Technical Field

The invention relates to a gas adsorption separation device, in particular to a device for concentrating organic waste gas pollutants by using an adsorption method and a specific application thereof.

Background

Adsorption gas concentration techniques are increasingly used in the field of pollution control of volatile organic compounds (VOCs, referred to herein simply as organic pollutants) in the atmosphere. Common gas adsorption concentration devices include rotating wheel adsorbers and regenerative fixed bed adsorbers. The ultimate goal of these gas adsorption concentration device designs is to concentrate the organic pollutant exhaust gas as much as possible and to achieve or lower the organic pollutant in the treated exhaust gas to or below the government regulated standard emission concentrations. In other words, the design goals for these devices include two: high concentration ratio and low emission concentration. If the adsorption bed should be allowed to adsorb as much organic pollutants as possible from the viewpoint of increasing the concentration ratio, in the extreme case all the adsorbents are allowed to reach saturation adsorption, the result is inevitably that the exhaust concentration of the treated exhaust gas is seriously exceeded, and in the worst case, the exhaust gas after treatment has the same concentration as the inlet exhaust gas in some regions (rotary adsorber) or for a certain period of time (regenerative fixed bed adsorber). The significance of pursuing high concentration ratio is that the organic pollutant concentrated gas with high concentration ratio is further processed, such as oxidation destruction, no addition is needed, so that the low-concentration fuel gas can be stably combusted, and the method comprises but is not limited to direct combustion, catalytic combustion, regenerative combustion or catalytic regenerative combustion; or the capacity of the gas to be treated can be reduced in the process of liquefying, capturing and recovering, thereby saving considerable cost. From the viewpoint of controlling the discharge concentration, it is necessary to shift to desorption before the organic contaminants penetrate the adsorbent bed and to completely desorb the organic contaminants in the adsorbent bed as much as possible during the desorption process, and in the extreme case, to completely desorb all the adsorbent in the adsorbent bed, and as a result, the concentration ratio is necessarily greatly reduced until there is no concentration effect at all or even a dilution process is performed. Since the desorption process is a dilution process in which the adsorbate concentration decreases exponentially in the thermodynamic principle, clean air with zero concentration of organic contaminants used for desorption also becomes contaminated air. All design options in real-life applications are tradeoffs between two extremes, achieving an acceptable process result between two opposing objectives of concentration ratio and emission concentration, depending on the actual parameters of the particular application. Fig. 1 is a functional partition diagram of an adsorption rotor, and the distribution of organic pollutant concentration along the section of the arcs of the adsorption zones a to B and the desorption zones C to D in the gas flow direction of the adsorption beds is roughly as shown in fig. 2. The large part of the airflow flowing out of the rotary wheel adsorption bed can not reach saturation when the rotary wheel adsorption bed is rotated out of the adsorption zone, and most of desorption gas passes through a region with very low saturation in the desorption zone. The concentration distribution of the organic pollutants in the regenerative fixed bed adsorber in the cross-sectional space perpendicular to the gas flow direction is ideally uniform theoretically, and the change law of the concentration of the organic pollutants in each linear area on the longitudinal section, which is consistent with the gas flow direction, on the time axis also conforms to the law shown in fig. 2.

Desorption, also known in the industry as desorption, is used herein in exactly the same sense.

Disclosure of Invention

The gas adsorption concentration device disclosed by the invention fundamentally solves the contradiction between the two goals, so that the gas adsorption concentration device can give consideration to both high concentration ratio and low emission concentration.

Referring to fig. 3, the basic structure of the gas adsorption separation device disclosed by the invention comprises an adsorption functional module 01 and other functional modules 02. The other functional modules 02 include a desorption device 021. The main functional part of the adsorption functional module is an adsorption sequence 011 consisting of more than two adsorption unit groups 09 arranged in sequence. The adsorption sequence 011 includes a head 0111 and a tail 0112 through which the gas to be treated 081 passes in a head-to-tail direction. When the adsorption unit at the head end finishes the saturated adsorption of the adsorbate gas, the adsorption unit is separated from the adsorption sequence 011 and enters a desorption device 021, and after the desorption treatment is finished, the adsorption unit enters the adsorption sequence 011 again from the tail end 0112 in sequence. The adsorption unit is an adsorption fixed bed which is composed of an adsorbent and a mechanical supporting structure and has proper mechanical strength and good permeability. The adsorption unit that completes saturated adsorption is referred to as saturated adsorption unit 091, and the adsorption unit that completes desorption regeneration is referred to as regenerated adsorption unit 092.

According to different specific applications, the gas adsorption separation device can adopt different adsorption and desorption modes according to different specific applications, mainly comprises temperature swing adsorption, pressure swing adsorption or temperature and pressure swing adsorption, and also can comprise some less common modes, mainly embodied in different desorption modes such as microwave desorption, displacement desorption and extraction desorption. Temperature swing adsorption is the process of concentrating or separating adsorbates by utilizing the difference in adsorption capacity of the adsorbent to the adsorbate at different temperatures, usually low temperature adsorption and high temperature desorption. Pressure swing adsorption refers to the concentration or separation of adsorbates by utilizing the difference in adsorption capacity of the adsorbent to the adsorbate under different partial pressures, and is usually high pressure adsorption and low pressure desorption. The temperature swing adsorption is a combination of the two, and is usually low-temperature high-pressure adsorption and high-temperature low-pressure desorption.

Referring to fig. 4, when the temperature swing adsorption-desorption method is used, the main functional part of the desorption apparatus 021 can be a desorption sequence 0211 consisting of more than two saturated adsorption cells 091 arranged in sequence, including a saturated end 02111 and a regenerated end 02112. The high temperature desorption gas 082 passes through the desorption sequence 0211 from the regeneration end 02112 to the saturation end 02111 to generate concentrated adsorbate gas 0821, and the regeneration adsorption unit 092 is generated to be separated from the desorption sequence 0211 after the saturated adsorption unit 091 completes desorption and regeneration. Thus, the high-temperature desorption gas 082 gradually transfers the heat carried by the high-temperature desorption gas 082 to the adsorbent of the adsorption bed when passing through the desorption sequence 0211, the temperature of the adsorbent is gradually increased, the adsorbate overflows, and the desorption is completed.

Referring to fig. 5-6, the desorption-completed regenerative adsorption unit 092 is in a high temperature state and needs to be lowered to a low temperature state to be suitable for re-entering the adsorption state. In the gas adsorption separation apparatus of the present invention, a thermal regeneration apparatus 022 may be disposed in the other functional modules, and the thermal regeneration apparatus 022 is configured to transfer heat contained in the high-temperature regeneration adsorption unit 092 to the source gas of the desorption gas 082, so that the source gas generates the desorption gas 082 after being thermally released. In practical applications, the main functional portion of the thermal regeneration device 022 may be a thermal regeneration sequence 0221 composed of two or more high-temperature regeneration adsorption units 092 arranged in sequence, and includes a hot end 02211 and a cold end 02212, the high-temperature thermal regeneration adsorption unit 092 completing desorption is added into the thermal regeneration sequence 0221 from the hot end 02211, and the thermal regeneration gas 083 passes through the thermal regeneration sequence 022 from the cold end 02212 to the hot end 02211, and is heated at a constant temperature to generate a high-temperature desorption gas 082, which enters the desorption device 021. The regenerative adsorption unit 092 that has completed the heat exchange exits the thermal regeneration sequence 0221 from the cold side and reenters the adsorption sequence 011 of the adsorption function module 01. It is also feasible if the thermal regeneration device 022 is configured to only comprise one regenerative adsorption unit, as shown in fig. 5, but the temperature reduction effect is not good enough and the thermal regeneration efficiency is low.

In the above technical scheme using the temperature swing adsorption principle, in the whole device operation process, including the adsorption process, the desorption process, the temperature reduction and the thermal regeneration process, the relative motion between the adsorbent and the working gas realizes the continuous and complete countercurrent mass and heat transfer process frequently adopted in the chemical field and the thermal field. The working gas here includes contaminated air and desorption gas. The key technical point of the invention is that the full countercurrent mass transfer in the adsorption process ensures that the adsorption unit which finishes the adsorption and enters the desorption process is in the saturated adsorption state under the working condition (mainly comprising the granularity of granular adsorbent or the wall thickness of a solid formed adsorbent channel interval, the concentration of the adsorbent, the air flow speed, the temperature and the like). "saturation" herein generally refers to dynamic saturation, i.e., the relative saturation state approaching static saturation that can be achieved under certain operating conditions under conditions that ensure operating efficiency and economy. This will primarily determine the maximum concentration of desorbed gas. The full countercurrent mass transfer heat transfer of the desorption process ensures that the regenerative adsorption unit that completes the desorption, i.e., is about to re-enter the adsorption process, is in a fully desorbed state at this operating condition (mainly including the particle size of the adsorbent or the wall thickness of the channel spacing, the desorption gas flow rate and temperature), which will mainly determine the minimum emission concentration of contaminated air for treatment. The low capacity of the desorption gas and the high concentration of organic contaminants will also reduce the energy consumption for its destruction by fire or recovery by coagulation. The full countercurrent heat transfer of the thermal regeneration process will reduce the thermal energy that must be consumed in the thermal regeneration of the adsorbent.

The present invention is further illustrated by the following specific examples.

Drawings

FIG. 1 is a structural schematic diagram of a zeolite runner.

FIG. 2 is a schematic diagram showing the distribution or change of adsorbate concentration during the operation of the zeolite rotating wheel and the regenerative fixed adsorption bed.

FIG. 3 is a schematic diagram showing the basic structural mode of the gas adsorption separation device.

Fig. 4 is a schematic diagram of the basic structural mode of the gas adsorption concentration device provided with a desorption sequence.

Fig. 5 is a schematic diagram of the basic structural mode of a gas adsorption concentration device provided with a desorption sequence and a thermal regeneration device.

Fig. 6 is a schematic diagram showing a basic structural mode of a gas adsorption concentration device provided with a desorption sequence and a thermal regeneration sequence.

FIG. 7 is a schematic structural diagram of a gas adsorption concentration device realized by the position movement between functional modules and provided with a regenerative combustion destroying device.

FIG. 8 is a functional block diagram of a unit moving device for moving the adsorption unit between the functional blocks in the gas adsorption concentration device shown in FIG. 7.

Fig. 9 is a schematic structural view of a gas adsorption concentration device provided with an adsorption unit storage supply device, a saturated adsorption unit recovery device, and a pressure reduction desorption device.

Fig. 10 is a schematic view showing the structure and operation mode of a gas adsorption concentration device for performing concentrated temperature rise desorption treatment.

FIG. 11 is a schematic view showing a structure of a gas adsorbing and concentrating device provided with a thermal regenerating device.

Fig. 12 shows the apparatus of fig. 11 modified to use a thermal regeneration sequence as the thermal regeneration means.

FIG. 13 is a schematic view of a gas adsorption concentration device implemented by switching disks through pipelines, which adopts the temperature swing adsorption principle.

FIG. 14 is a schematic view of a gas adsorption and concentration device implemented by switching disks through pipelines, and adopting a temperature and pressure swing adsorption principle.

Detailed description of the invention

Example 1

A unit mobile gas adsorption concentration device, see figures 7-8.

See fig. 7. The device comprises an adsorption device 11, a desorption device 12, a saturation transition cavity 13 and a regeneration transition cavity 14. The adsorption device 11 includes an adsorption cavity 111 and an adsorption sequence 112 contained in the adsorption cavity, the adsorption sequence 112 includes a head end 1121 and a tail end 1122, the adsorption sequence includes more than two adsorption units 1113, and a unit at the head end that completes saturated adsorption is a saturated adsorption unit 11131.

The desorption device 12 includes desorption sequence 122 that desorption chamber 121 and desorption intracavity hold, and desorption sequence 122 includes saturation end 1221 and regeneration end 1222, and the desorption sequence includes more than two in desorption adsorption unit 1223, and the adsorption unit that is located the completion desorption of regeneration end is regeneration adsorption unit 12231.

The two ends of the adsorption cavity 111 and the desorption cavity 121 are respectively communicated by the saturation transition cavity 13 and the

regeneration transition cavity

14, and 1 valve capable of allowing the adsorption unit to pass through is respectively arranged at the connection part of the two cavities, wherein the valves are respectively 151, 152, 153 and 154. The functions of the saturation transition cavity 13 and the regeneration transition cavity 14 are to complete the transfer of the adsorption unit between the two chambers under the condition that the adsorption device 11 and the desorption device 12 are kept working continuously and avoid the occurrence of the cross mixing of the polluted gases in different treatment states between the two chambers. If an intermittent mode of operation is used, i.e. the adsorption unit is transported with the pollutant gas treatment stopped, two transition chambers can be eliminated.

The adsorption and desorption of this example are performed by temperature swing adsorption.

This gas adsorbs enrichment facility during operation and adsorbs the chamber and desorbs the chamber and all fill up the absorption unit, and large-traffic pending gas passes the absorption sequence that is located the absorption intracavity from adsorbing sequence 112 head end 1111 to tail end 1112, and when the absorption unit that is located the head end reached saturation absorption, valve 151 between absorption chamber and the saturation transition chamber was opened, and mechanical device pushed this saturation absorption unit 11131 into the saturation transition chamber, and valve 151 closes, and mechanical device passes whole absorption sequence to the head end. The valve 153 between the desorption cavity and the regeneration transition cavity is opened, the mechanical device pushes the regeneration adsorption unit 12231 at the regeneration end of the regeneration sequence into the regeneration transition cavity, the valve 153 is closed, the mechanical device pushes the desorption sequence in the desorption cavity towards the regeneration end, and the saturation end of the desorption cavity is free. The valve 152 between the saturation transition chamber and the desorption chamber is opened and a mechanical device pulls the saturation adsorption unit 11131 into the desorption chamber. The valve 154 between the saturation transition chamber and the adsorption chamber is opened and a mechanical device pulls the regenerative adsorption unit 12231 in the regeneration transition chamber into the adsorption chamber. In the above order, the adsorption unit was cyclically moved in 4 chambers. In the whole process, the small-flow high-temperature desorption gas passes through the desorption sequence in the desorption cavity from the saturation end to the regeneration end without interruption. The flow ratio of the gas to be treated and the high-temperature desorption gas in the gas adsorption concentration device may be 10: 1 to 50: 1 or higher. The organic pollutants contained in the high-temperature desorption gas are generally sent to a combustion destroying device for destruction if the organic pollutants are components which are suitable for combustion and have low recovery value. Fig. 18 is a schematic structural view of a regenerative burner. The combustion destroying device can also be a direct burner, a catalytic burner or a regenerative catalytic burner according to the difference of the calorific value of the desorbed gas and the combustibility of the organic matters. If the calorific value of the desorbed gas is high enough, the combustion destruction process of the organic pollutants can also provide heat for heating the desorbed gas. This is also one of the final objectives of the technical improvements made by the present invention.

The transfer of the adsorption unit between the 4 chambers can be automated by a series of conventional power mechanisms. Referring to fig. 8, 4 hydraulic or pneumatic push rods may be used in this embodiment, wherein the push rods for pushing the adsorption unit to move in the adsorption or desorption chamber are 181-1 and 181-2, respectively. The push-pull rods that push or pull the adsorption units to move among the adsorption chamber, the desorption chamber, the saturation transition chamber and the regeneration transition chamber are 182-1, 182-2-182-3 and 182-4, respectively.

The valves between the transition chamber and the adsorption and desorption chambers in fig. 7 are schematically shown by double-opening rotary doors, and the valves are hydraulic or pneumatic gate valves in practical application in the embodiment, and are numbered as 151-1, 152-1, 153-1 and 154-1 in the figure.

Example 2

Unit feed and recovery gas adsorption concentration devices, see fig. 8-9.

One of the important conditions for the specific application of the gas adsorption concentration device shown in the embodiment is that the flow rate and the concentration of the organic pollutants in the waste gas to be treated are basically stable, because the thermal desorption needs to utilize the organic pollutants in the waste gas as heat-generating fuel to maintain a basically stable high-temperature environment. If the exhaust gas is discharged intermittently or the flow rate and concentration fluctuate greatly, the desorption process is adversely affected, and additional supplementary fuel is usually required. The unit feed and recovery gas adsorption concentration device disclosed in example 2 can be excellently adapted to this situation.

The specific scheme of the unit feeding and recovery type gas adsorption concentration device is that the adsorption device 11 and the desorption device 12 of the gas adsorption concentration device are divided into two independent parts, and an adsorption unit turnover device 16 is added, and comprises an adsorption unit feeding device 161 and an adsorption unit recovery device 162. The mechanical structure of the unit transfer device 16 can be referred to as the magazine structure of the firearms to be fired. The saturated adsorption unit 191 of the adsorption apparatus 11, which has completed saturated adsorption at the head end of the adsorption sequence, is moved by a mechanical device into the closed adsorption unit recovery apparatus 162 connected to the adsorption chamber through a valve, and a new or regenerated adsorption unit 192 is replenished to the adsorption chamber from the adsorption unit supply apparatus 161 connected to the adsorption chamber through a valve. After the adsorption unit recovery device is full of the saturated adsorption unit, the saturated adsorption unit is moved to the independent desorption device 12 to perform desorption treatment on the saturated adsorption unit. The desorption unit may be connected to a vacuum pump 194, a compression and condensation unit 195 and a storage unit 196 to recover the separated organic contaminants, as shown in fig. 9. Or the adsorption single recovery devices which are generated by a plurality of gas adsorption devices and are filled with the saturated adsorption units can be centralized at one desorption device, and the desorption treatment can be continuously carried out in a thermal desorption mode, as shown in the attached figure 10. In short, the desorption device can adopt any suitable desorption mode including thermal desorption, reduced pressure desorption, thermal reduced pressure desorption, replacement desorption and the like.

Example 3

A thermal regeneration gas adsorption concentration device, see figures 11-12.

The regeneration adsorption unit that completes desorption in the gas adsorption concentration device shown in example 1 enters the regeneration chamber through the transition chamber and is still in a high temperature state when an adsorption sequence is added, although the polluted air that has basically completed adsorption with a large flow rate can quickly take away the heat thereof and cannot cause significant influence on the adsorption process, the loss of the system heat energy is caused, which has a certain negative influence on the reduction of the energy consumption of one of the original purposes of the device.

The technical scheme for overcoming the technical defect is that a thermal regeneration device 17 is used for replacing the regeneration transition cavity 14 in the embodiment 1, and the heat contained in the high-temperature regeneration adsorption unit is carried and transferred to an adsorption sequence by using regeneration gas, which is shown in figure 10. Specifically, an air inlet 172 and an air outlet 173 are provided on the left and right surfaces of the transition chamber, respectively, and the air filtered by the air filter 174 passes through the regeneration adsorption unit in the thermal regeneration device 17, is pressurized by the fan 175, is heated by the heat exchanger 176, and enters the desorption chamber 121.

Referring to fig. 11, in order to further improve the heat regeneration efficiency of the heat regeneration device, a heat regeneration sequence 171 may be disposed in the heat regeneration device. Thermal regeneration sequence 171 comprises more than two regenerative adsorption units, including a hot side 1711 and a cold side 1712. The hot end 1711 is communicated with the regeneration end 1212 of the desorption cavity 121 through a valve. The cold end 1712 is in communication with the tail end 1112 of the adsorption chamber 111 through a valve. The movement transmission manner of the adsorption unit can be referred to embodiment 1.

Example 4

A rotating disc type temperature swing adsorption gas adsorption concentration device, see figure 12.

This embodiment replaces the mechanical device for transporting the adsorption unit of embodiment 3 with a set of pipeline switching disks and a series of stop valves, and can also achieve the saturated adsorption of air pollutants, and the adsorption sequence and desorption sequence, and if necessary, can also include a thermal regeneration sequence, in which the complete countercurrent mass and heat transfer process between the adsorbent and the working gas.

The device comprises a rotating base 21 which can be driven by power to rotate discontinuously, wherein the rotating direction is clockwise, a point on a relative disc is specified, the other point positioned on the clockwise direction is a clockwise side, and the other point positioned on the counterclockwise direction is a reverse side. 6 fixed bed adsorbers 22-1, 22-2, 22-3, 22-4, 22-5 and 22-6 are fixed on a rotary base 21 in a central symmetry manner and are communicated into a closed ring through pipelines, a stop valve 23 capable of automatically controlling opening and closing is arranged in the middle of each section of pipeline connected with the fixed bed adsorbers, a switching pipe 24 leading to the periphery of the rotary base 21 is respectively arranged at the two ends of the forward side and the reverse side of each fixed bed adsorber, the number of the switching pipes is 12, and a rotary part 251 for switching the stop valves is arranged at the outer end of each switching pipe 24. Outside the swivel base 21, 6 fixing portions 252 for switching shutoff valves fixed to the floor surface are provided. The complete switching stop valve 25, which is composed of the rotating part 251 and the fixed part 252, has two functions of rotating switching and stopping opening, and can be replaced by an independent stop valve arranged on a rotating base and a switching valve composed of two parts respectively arranged on the rotating base and the ground. The rotary valve can be referred to a commercial rotary four-way steering valve, and is distinguished from switching between 4 passages into switching of a plurality of passages, and when the rotary part rotates to a position without a fixed part corresponding to the rotary part, a blocking device is arranged at a position corresponding to the fixed part to block the rotary part.

The 6 fixed bed adsorbers are divided into 3 groups, wherein 22-1, 22-2 and 22-3 are adsorption groups, 22-4 and 22-5 are desorption groups, and 22-6 is a thermal regeneration group. The number of the fixed part 252 of the switching stop valve corresponds to the number of the fixed bed adsorber, the forward side is numbered as 252-XA, the reverse side is numbered as 252-XB, and X is the serial number of the fixed bed adsorber. The contaminated air supply pipe 261 communicates with the fixing portion 252-3A of the switching stop valve, the treated contaminated air discharge pipe 262 communicates with the fixing portion 252-1B of the switching stop valve, the regeneration air supply pipe 263 communicates with the fixing portion 252-6A of the switching stop valve, the desorption air heating pipe extraction and input ends 264, 265 communicate with the fixing portion 252-6B of the switching stop valve and the fixing portion 252-5A of the switching stop valve, respectively, and the desorption gas discharge pipe 266 communicates with the fixing portion 252-4B of the switching stop valve. 3 stop valves are opened between 3 fixed bed adsorbers in the adsorption group and between two fixed bed adsorbers in the desorption group, and 3 stop valves between other groups are closed. The desorbed gas discharge pipe is communicated with an air inlet pipe 271 of the regenerative burner 27, and a flue gas discharge pipe 272 of the regenerative burner 27 is communicated with the treated polluted air discharge pipe 262 in parallel with a chimney (not shown).

In operation, contaminated air enters from the contaminated air supply pipe 261 and is discharged from the treated contaminated air discharge pipe 262 through the 3 adsorption groups of fixed-bed adsorbers 22-3, 22-2, and 22-1 in sequence. The regeneration air enters from the regeneration air supply pipe 263, passes through the thermal regeneration group fixed bed adsorber 22-6, is heated by the regenerative combustion furnace 27, passes through the desorption group fixed bed adsorbers 22-5 and 22-4, is discharged from the desorption gas discharge pipe 266, is introduced into the regenerative combustion furnace 27, burns and destroys the organic pollutants carried in the regeneration air, passes through the smoke discharge pipe 272, flows with the treated polluted air and flows through the chimney to be discharged into the high-altitude atmosphere. After a certain operating time or after the device receives a certain amount of organic pollutants, the adsorption capacity of the fixed bed adsorber 22-3 is saturated, the rotating base 21 rotates 60 degrees, and the adsorbers are grouped again.

One fixed bed adsorber completes the entire process cycle through 6-step transitions, with the time between each adjacent two transition events being referred to as 1 process interval.

After the fixed bed adsorber enters an adsorption sequence, the head end of the fixed bed adsorber is moved from the tail end of the adsorption sequence through 2 times of conversion in 2 processing intervals, saturation adsorption is completed in one processing interval, the fixed bed adsorber enters the saturation end of a temperature rising desorption sequence through 3 times of conversion, the fixed bed adsorber runs to the regeneration end of the temperature rising desorption sequence through 4 times of conversion in one processing interval, the fixed bed adsorber is converted into a heat regeneration interval through 5 times of conversion in one processing interval, the number of the heat regeneration intervals is only 1, and the fixed bed adsorber is converted into the next cycle again after the heat regeneration interval is completed.

Example 5

A rotating disc type temperature and pressure swing adsorption gas adsorption recovery device, see figure 12.

The rotating disk temperature swing adsorption gas adsorption concentration device shown in example 4 has its limitations if faced with the following two specific applications. Firstly, the polluted air contains organic pollution gas which is not easy to destroy by a combustion method, such as sulfur, phosphorus and halogen elements or benzene rings and chlorine elements, and the gas generates secondary pollutants after combustion. Secondly, the pollutants contain enough high-value organic pollution gas, and have recycling value.

The embodiment discloses a gas adsorption recovery device for eliminating air pollution and simultaneously recovering organic pollutants by using a temperature and pressure swing adsorption method.

The air-dyed adsorption group of the device is similar to the device shown in the embodiment 4, only one treatment period is added, the device is mainly different in that a heat regeneration group is eliminated, and the function setting of the ground fixing device in the desorption area is changed. The desorption group of the device comprises two treatment periods, a circulating air heating interval and a vacuum desorption interval. The device corresponding to the circulating air heating section comprises a hot blast stove 291, a fan 292 and a pressure reducing valve 293. The ground fixtures corresponding to the vacuum desorption interval are a throttle valve 297, a vacuum pump 294, a condenser 2951, and a liquid storage tank 296.

After the hot blast stove 291 and the fan 292 are connected in series, two ends are respectively communicated with the switching pipes 24 at two ends of the fixed bed adsorber 22 in the circulating air heating interval through the switching stop valve 25. The vacuum pump 294 and the throttle valve 297 are connected to the switching pipes 24 at both ends of the fixed bed adsorber 22 in the vacuum desorption zone, respectively, through the switching shutoff valve 25. The pressure reducing valve 293 is communicated with a pipeline between the circulating air heating section and the vacuum desorption section. A condenser 295 and a liquid storage tank 296 are connected in sequence after the vacuum pump. The liquid discharge port of the condenser 295 is connected to a liquid storage tank 296, and the noncondensable gas discharge port is communicated with the contaminated air supply pipe 261.

After the fixed bed adsorber finishes saturated adsorption, the fixed bed adsorber rotates to a circulating air heating interval, the air is heated by a hot blast stove and a fan, the temperature of an adsorption bed is gradually increased, organic pollutant gas released by an adsorbent and gas thermal expansion have the tendency of causing the air pressure in a pipeline to be increased, and the gas is decompressed by a decompression valve and then enters a vacuum pump together with the gas exhausted by the fixed bed adsorber in a vacuum desorption interval. And after the fixed bed adsorber finishes the heating of circulating air, the fixed bed adsorber rotates to a vacuum desorption interval, organic pollutant gas is continuously released under low pressure caused by a vacuum pump, and a small amount of air is input in a controlled manner through a throttle valve when the vacuum desorption is nearly finished, so that the residual organic pollutant gas is further washed out. The mixed gas containing organic pollutant gas exhausted by the vacuum pump is separated into organic pollutant liquid by the condenser, and the organic pollutant liquid flows into the liquid storage tank to be collected and stored. The non-condensable gas discharged from the condenser possibly contains a small amount of organic pollutants, and the non-condensable gas is merged into a polluted air input pipe for cyclic adsorption and purification.

Claims

1. A gas adsorption separation device is characterized by comprising an adsorption function module and other function modules, the main functional part of the adsorption functional module is an adsorption sequence consisting of more than two adsorption units which are arranged in sequence, the adsorption sequence comprises a head end and a tail end, the gas to be separated passes through the adsorption sequence from the head end to the tail end, when the adsorption unit at the head end finishes the saturated adsorption of the adsorbate gas, the adsorption unit is separated from the adsorption sequence and enters other functional modules comprising a desorption device, and re-enter the adsorption sequence from the tail end in sequence after other process treatments including desorption treatment are completed, the adsorption unit is an adsorption fixed bed which is composed of an adsorbent and a mechanical support structure and has proper mechanical strength and good permeability, the adsorption unit which completes saturated adsorption is called a saturated adsorption unit, and the adsorption unit which completes desorption regeneration is called a regeneration adsorption unit.

2. The gas adsorption separation device of claim 1, wherein the adsorption and desorption method is one of temperature swing adsorption, pressure swing adsorption and temperature swing adsorption.